Abstract: -650 development tunnel in a mine with the more complex geological condition was affected by the nearby coal face of mining, and severe deformation of the surrounding rock has occurred.Two detection steps were divided that the detection of prophase fractured rock zone and late drilling visualization, the broken-rock circle and fracture development were obtained, comparative analysis derived the surrounding rock mass range extension to the deep, to be large circle, even to occur loose destruction phenomenon.Based on deep surrounding rock deformation laws and its mechanical properties, in surrounding rock stability control theory of the soft rock tunnel, to create tunnel force model and to analysis the force relationships, on which “Pass beam” structure in slop direction of face and “Part block” structure of roof after two faces roof caving.Combing with drilling detection results and observation phenomenon, summed up the tunnel deformation characteristics and result in deformation of surrounding rock.It provides science guidance and theoretical basis in secondary support, and was referenced of the similar ones.

Key words: Large deformation, Influence of mining, Soft rock tunnel, Loose zone, Secondary support